Method and apparatus for laying a pipe line

ABSTRACT

The present invention relates to a method and apparatus for laying a pipe line including a weighted sled having a vertical blade extending therebelow with an extruder cone affixed to its lower end for forming a subterranean tunnel for receiving a pipe. The blade is provided with a plurality of spaced jet nozzles connected to a fluid manifold for providing high pressure jet streams adjacent the leading edge of the blade to facilitate movement of the blade through earthen formations. Also, the blade is provided with a plurality of spaced inclined elevator devices for urging the soil adjacent the blade upwardly as the blade moves therethrough to relieve the soil adjacent the extruder cone and thereby facilitate formation of the tunnel passage therethrough. The method of the present invention includes treating the interior of the tunnel with a weighted low friction coefficient fluid or aqua gel to lubricate the passage to facilitate insertion of the pipe into the tunnel without damaging the coating on the pipe.

United States Patent 1 Holberg l l METHOD AND APPARATUS FOR LAYING APIPE LINE [76] Inventor: Robert E. Holberg, 608 W. Bough Lane, Houston,Tex. 77024 [22] Filed: Dec. 6, 1971 [21] App]. No.: 205,210

[52] US. Cl 61/72.4, 37/193, 172/699 [51] Int. Cl E02f 5/02 [58] Fieldof Search 6l/72.4, 72.1, 72.5, 72.6, 61/72.7; 37/193; 172/699, 700, 730

[56] References Cited UNITED STATES PATENTS 184,171 11/1876 Porterl72/7OO 3,181,301 5/1965 Davis... 61/72.4 3,589,135 6/1971 Ede 6l/72.11,808,974 6/1931 Wilkens 37/193 3,268,012 8/1966 Ratkowski.... 172/7003,684,030 8/1972 Lucero 37/193 FOREIGN PATENTS OR APPLICATIONS 402,50612/1933 Great Britain 37/193 279,462 11/1964 Netherlands 172/700 [1113,788,085 1 Jan. 29 ,1974

Primary Examiner-Jacob Shapiro Attorney, Agent, or Firm-Pravel, Wilson &Matthews 57] ABSTRACT The present invention relates to a method andapparatus for laying a pipe line including a weighted sled having avertical blade extending therebelow with an extruder cone affixed to itslower end for forming a subterranean tunnel for receiving a pipe. Theblade is provided with a plurality of spaced jet nozzles connected to afluid manifold for providing high pressure jet streams adjacent theleading edge of the blade to facilitate movement of the blade throughearthen formations. Also, the blade is provided with a plurality ofspaced inclined elevator devices for urging the soil adjacent the bladeupwardly as the blade moves therethrough to relieve the soil adjacentthe extruder cone and thereby facilitate formation of the tunnel passagetherethrough. The method of the present invention includes treating theinterior of the tunnel with a weighted low friction coefficient fluid oraqua gel to lubricate the passage to facilitate insertion of the pipeinto the tunnel without damaging the coating on the pipe.

5 Claims, 6 Drawing Figures METHOD AND APPARATUS FOR LAYING A PIPE LINEBACKGROUND OF THE INVENTION 1. Field of the Invention The presentinvention relates to a method and apparatus for forming a subterraneantunnel for receiving a buried pipe line and a method for inserting thepipe into such tunnel.

2. Summary of the Prior Art The prior art is believed to be exemplifiedby the following US. Pat. Nos. 178,231 to Campbell; 354,429 to McMullin;369,783 to Fisk; 815,163 to Hatfield;

SUMMARY OF THE INVENTION The present invention comprises a new andimproved method and apparatus for forming a subterranean tunnel inremote places, such as beneath the bed of a river or other body ofwater, for receiving a pipe or other conduits so as to lay a pipe linetherein. With this invention, laterally extending inclined surfaces areprovided adjacent the sides of the vertically extending blade for movingsoil and earthen formations adjacent thereto to facilitate the extrusionof soil around the plow foot which forms the tunnel or passage forreceiving the pipe or conduit. Further, a plurality of vertically spacedjets are provided at the leading edge of the vertical blade for jettingand cutting the soil immediately ahead of the blade to facilitatepassage of the blade therethrough when forming the pipeline tunnel. Suchvertical blade is supported by a weighted sled having an upturned noseor leading surface for riding over obstacles on the surface of the riverbed or other soil formation on which the plow is used and also to engagethe surface of the earth to support the tunnel extruding device at apredetermined elevation therebelow.

With the apparatus of this invention, a subterranean tunnel may beformed in the earth for receiving a pipe or other conduit with a minimumdisturbance of the over burdening soil and the surface and which enablesa pipeline to be laid beneath the surface of a river or other waterbody.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a view partly in section showingthe pipeline plow apparatus being pulled through the earth to form asubterranean tunnel and placing a pipe therein;

FIG. 2 is an isometric view of the plow sled with the blade dependingtherefrom;

FIG. 3 is a plan view of the pipeline plow sled;

FIG. 4 is an isometric view of the plow blades showing the sideelevators and also the extrusion cone at the foot;

FIG. 5 is a rear view of the blade shown in FIG. 4; and

FIG. 6 is a sectional view taken on line 66 of FIG. 5 showing details ofconstruction of a remotely actuated disconnect for disconnecting astring of pipe from the plow blade.

DESCRIPTION OF THE PREFERRED EMBODIMENT Briefly, the pipeline plowapparatus of the present invention, which is designated generally P inFIGS. 1 and 2 of the drawings, comprises a sled S having a substantiallyvertically extending blade B depending therebelow for supporting anextruding cone E at a predetermined elevation beneath the ground line Gfor forming a subterranean tunnel T for receiving a pipe or otherconduit. The sled S is moved along the ground line G, which may be thebed of a water body or the surface of dry ground, by means of a cable Cwound on a winch W. A bull plug B secured to the aft end of the extrudershoe E is provided for pulling a string of pipe L into the tunnel formedby the extruder E.

Considering now the apparatus of the present invention in more detail,the plow sled S preferably comprises a longitudinally extending platformhaving a substantially flat bottom 13 with an upwardly inclined leadingbow section 14 for enabling the bow to roll or slide over obstructionswhich may lie in its path. The sled includes a vertically disposed pullbeam member 18 which extends axially of the sled S and projects upwardlyfrom the deck 19. The beam 18 is preferably welded to the deck 19 andextends rearwardly from the bow section 14 and includes blade pocket 20that comprises a vertical opening or passage that extends through thebody of the'sled S for receiving the blade B. With the blade positionedin the pocket, it is affixed to the beam 18 by means of a plurality ofremovable pins 30 which extend through suitable openings 21, 22 and 23in the upper end of the blade B and which are received in correspondingopenings 21a, 22a and 23a in the beam 18. As shown, the pull eye 30 towhich the cable C is affixed is positioned at the forward end of thebeam 18 and in line therewith for applying the pull forces axially ofthe beam.

The body of the sled is preferably provided with a compartment 40 forreceiving high density concrete to reinforce and stabilize the sledadjacent the pocket through which the blade extends to minimize orsubstantially eliminate oscillations or vibrations which may be set upin the plow and to provide a substantial counterweight aft of the bladeB to assist in holding the blade in the ground at the desired elevationand to aid in forming the extruded tunnel T as will be described indetail hereinafter. The counterweight can vary in size according to soilconditions, however a substantial weight such as approximately 15,000pounds has been found to be beneficial in preventing the sled fromriding up so as to elevate the extruder above the desired depth, whichis usually from 4 to 8 feet below the ground line G. The compactingaction of the weighted sled also tends to fix the soil above the tunneland thereby reduce or eliminate the need for a weight coat on the buriedpipe.

As best seen in FIG. 3 of the drawings, the aft end of the sled S isprovided with a central or axially disposed channel or opening 50 whichextends from the aft end 51 of the sled to adjacent the aft end of thepocket 20 so that the counterweight formed in the compartment 40 is notdisposed directly above the tunnel formed by the extruder E. Further, acathedral trough or inverted V-shaped opening 60 formed by upwardly andinwardly inclined sides or walls 61 which extend from the bottom 13upwardly toward the top of the compartment 40 to provide space for anysoil which is moved upwardly by the plow blade B and extruder E to bedisplaced slightly above the surface of the ground level G as will beexplained in detail hereinafter.

The blade B comprises a steel plate having a tapered or relieved leadingedge 70 with a plurality of cutting jets 71 positioned adjacent theretoso as to provide a series of jets for cutting the soil adjacent theleading edge of the blade B to facilitate its movement therethrough.Such jets are connected to a supply manifold 74 by means of suitableconduits 73 disposed on opposite sides of the blade B and affixedthereto. The supply manifold 74 is positioned on the trailing or aftedge of the blade B and connected to a remote pressure source (notshown) for supplying water or other fluid under pressure atapproximately 10,000 psi to each of the jets 71.

Also, as shown in FIGS. 4 and 5 of the drawings, a plurality of shortelevators 75 are provided on opposite sides of the blade B fordisturbing or elevating the soil on either side of the blade as it movestherethrough. Such elevators preferably comprise relatively short vaneswhich project laterally from the sides of the blade B and which areinclined at an angle of approximately from 17 to 22. The elevators 75are preferably arranged so that each elevator is positioned slightlyrearwardly of the elevator immediately thereabove so as to provide aseries of vanes, each set at substantially the same angle and arrangedin a substantially diagonal line across the faces or sides of the bladeB so as to provide a means for cutting or disturbing the soil beneaththe sled and adjacent the sides of the blade over substantially its fullsubmerged depth in the soil.

A diving vane 77 is positioned beneath the elevators E to facilitateholding the extrusion shoe E at a desired depth beneath the ground lineG and for also relieving or disturbing the soil immediately thereaboveto facilitate extrusion of the soil around the periphery of theextrusion cone E as will be described. It has been found that suchdiving vane should be substantially within the range of 17 to 22 fromhorizontal in order to best function as a means for holding theextrusion head E in its proper submerged position and to facilitate themovement of the extrusion head through the adjacent soil.

As shown the extrusion cone E is positioned at the foot of the blade Band rearwardly of the cutting tooth K. Such cutting tooth K preferablycomprises a triangular or wedge-shaped point 78 formed integrally withthe blade B and projecting forwardly of the leading edge 70. The foot orbottom of the cutting tooth K is preferably relieved slightly so as toavoid frictional engagement of the bottom surface 79 with the soiladjacent thereto. The top of the tooth K includes a wedgeshaped point 80affixed to the forward end of the wedge-shaped portion 78. A cap orplate 82 is welded or otherwise affixed to the upper inclined surface78a of the wedge-shaped portion 78 and is wider than the plate formingthe blade B so as to project laterally on either side thereof. Theextrusion cone E is positioned rearwardly of the wedge-shaped portion 78of the tooth K at the foot of the blade B. As shown in FIG. 6, suchextrusion head E is shaped so as to form an eliptical cross section withits longer axis in a vertical plane and its shorter axis in a horizontalplane. The conical eliptical-shaped extrusion member is welded to theblade B and is provided with a pair of laterally projectinglongitudinally extending vanes 81 which are inclined at substantiallythe same angle as that of the diving vane 77. Further, the elipticalextrusion cone is positioned on the blade B so the bottom edge 79projects below the cone to form a vertically projecting longitudinallyextending bottom vane beneath such extrusion member B.

As shown in FIG. 6 of the drawings, the apparatus for releasablyattaching the leading end of the string of pipe to the extrusion footcomprises a cap or bull plug which is normally welded onto the end ofthe pipe 91. Such plug includes an axially extending eye pin 92 having aloop or opening 93 therein for receiving the locking member 95. Such eyemember 92 is inserted between parallel plates 97 and 98 which are weldedor otherwise attached to the conical extruder E. As shown, the lockingmember comprises a conical or tapered pin which is inserted through theopening 93 in the eye member 92 for locking and securing the eyethereto. A remote actuating device designated generally 100 is alsoprovided for releasing or withdrawing the lock member or pin 95 from theopening 93 so as to enable the pipe 91 to be disconnected from theextruder E when the pipe is several feet beneath the ground line G whichin some instances may also be many feet below the surface of theoverlying water body. Thus, it can be appreciated that in the event theplow should encounter some obstruction or if the pipe should for somereason become stuck at some point along the course short of the finaldestination, the pipe can be disconnected from the eliptical extrusionmember E. An operation rod 103 is connected to the tapered pin 95 andextends upwardly along the aft edge of the blade B through a pluralityof spaced guides 104 to an actuating cam 105 pivotally mounted at theupper end of the blade B. An operating arm 106 is also connected to thecam 105 for rotating the cam to raise the rod 103 and disconnect thepipe from the plow.

In using the plow of the present invention for forming a subterraneantunnel for receiving a submerged pipeline, particularly in remotelocations such as beneath the bed of rivers or other water bodies, asuitable bell hole is prepared sufficiently far back on the bank toprevent surface water from flowing into the bell hole and a slide orlaunching approach of approximately 12 grade from the bottom of theriver up to the bell hole is also prepared and the sled with the plowblade set at the required depth for the extrusion head is placed inposition for entering the river bed. A suitable length of pipeline formaking the crossing is welded together, coated, tested and placed onpipe dollies or skids and thereafter the pipe is connected to the pullplug on the bottom of the plow. The sled is then pulled across the riverwith the necessary cables operated by the winch. With the sled followingthe grade of the river bed, the extrusion head prepares the extrudedtunnel at the preset depth below the river bed. The extrusion head E isnormally 4 inches larger in side diameter than the pipe which is to bepulled through the tunnel behind it. Of course, it will be appreciatedthat the number of lines and sheaves required to make each pull may varyaccording to the pipe size and the soil conditions to be encountered.However, by pulling on the cable or line from the draw works or winch,the sled is drawn along the surface of the ground with the extrusionhead buried at the desired depth. It will also be appreciated that thelaterally projecting elevators as well as the larger diving vane willdisplace soil adjacent the plow blade and on opposite sides thereofvertically upwardly as the blade is drawn through the earth so as torelieve the overburden and thereby facilitate extrusion of the tunnel bymovement of the extruder head through the soil beneath the area which isdisturbed by the blade and the vanes projecting laterally therefrom.Further, it will be appreciated that by providing the inverted V-shapedopening in the bottom of the sled aft of the blade that space will beprovided for receiving soil which may be extruded upwardly on oppositesides of the blade and further, that the weighted sled will not beardirectly upon the soil adjacent the blade which is being displaced orextruded upwardly. The weighted sled is arranged so that the opening 51spaces the weighted portions on opposite sides of the trench therebyproviding a counterweight or compacting force on the soil adjacent thepath of the tunnel.

Further, it will be appreciated that a suitable portable high pressurefluid system may be carried on a suitable flotation member during rivercrossing so as to provide a source of high pressure fluid to the jetswhich jet the earthen formations immediately in front of the leadingedge of the blade. Also, in some instances it is desirable reduce thehazards of sticking the pipe in a partially 7 completed tunnel. Afterthe first pass has been made with the plow to prepare the extrudedtunnel, then on a second pass the plow is guided through substantiallythe same course with the pipe attached to the foot of the plow.

It has also been found that to facilitate the insertion of a coated pipeinto the extruded tunnel without unnecessarily damaging or breaking awrap or protective coating formed on the pipe that an aqueous, viscousfluid or gel coat may be injected into the tunnel to form a lubricatingmeans for sliding the pipe through the tunnel with a minimum offrictional drag. in some instances where the extruded tunnel is plowedwithout the pipe being attached to the plow the lubricating gel ispumped into the tunnel and such lubricating gel has a specific gravitygreater than one so as to displace any water that may be in the tunneland thereby remain in place until the pipe is placed in the tunnel anddisplaces some of the weighted viscous fluid.

The foregoing disclosure and description of the invention areillustrative and explanatory thereof, and various changes in the size,shape and materials as well as in the details of the illustratedconstruction may be made without departing from the spirit of theinvention.

What is claimed is:

1. An underwater plow for forming a subterranean tunnel beneath a waterbody for receiving a conduit comprising:

a. a sled having a substantially flat bottom adapted to engage asubmerged bottom surface and having an upturned bow to facilitatemovement along such submerged bottom surface and to support an extruderhead a substantially predetermined distance below said bottom surface;

b. a vertically disposed plow blade having a leading edge and a trailingedge extending beneath the bottom of said sled and rigidly affixedthereto;

c. a plurality of lateral productions on the sides of said blade fordisplacing the earthen formations adjacent to said blade as it passestherethrough;

d. extruder head means at the foot of said blade for forming asubterranean bunnel in the earth a substantially predetermined distancebelow such ground surface; and i e. longitudinally extending inclineddiving vanes projecting laterally from the opposite sides of the plowblade and extending substantially from the leading edge to the trailingedge thereof for urging said blade downwardly as it is moved through theearth so as to secure said sled to a river bed.

2. The invention of claim 1 wherein said means at the foot of said bladefor forming a subterranean tunnel comprises a wedge-shaped blade memberprojecting forwardly of the leading edge of said blade with an elipticalcone member. positioned aft of said wedge member and disposed with thelonger axis of said elipse substantially parallel to the plane of saidblade.

3. The invention of claim 2 including longitudinally extending laterallyprojecting vanes positioned in a substantially horizontal plane onopposite sides of said eliptical cone.

4. The invention of claim 3 wherein said diving vane is inclined at anangle of 17 to 22 with respect to the base of said sled.

5. The invention of claim 1 including means for releasably connecting astring of pipe to the foot of said blade includes an eye member adaptedto receive a tapered pin with rod means connecting said pin to anactuating cam at the top of said blade to permit withdrawing said pinfrom said eye from a remote location above the earth s surface.

1. An underwater plow for forming a subterranean tunnel beneath a water body for receiving a conduit comprising: a. a sled having a substantially flat bottom adapted to engage a submerged bottom surface and having an upturned bow to facilitate movement along such submerged bottom surface and to support an extruder head a substantially predetermined distance below said bottom surface; b. a vertically disposed plow blade having a leading edge and a trailing edge extending beneath the bottom of said sled and rigidly affixed thereto; c. a plurality of lateral productions on the sides of said blade for displacing the earthen formations adjacent to said blade as it passes therethrough; d. extruder head means at the foot of said blade for forming a subterranean bunnel in the earth a substantially predetermined distance below such ground surface; and e. longitudinally extending inclined diving vanes projecting laterally from the opposite sides of the plow blade and extending substantially from the leading edge to the trailing edge thereof for urging said blade downwardly as it is moved through the earth so as to secure said sled to a river bed.
 2. The invention of claim 1 wherein said means at the foot of said blade for forming a subterranean tunnel comprises a wedge-shaped blade member projecting forwardly of the leading edge of said blade with an eliptical cone member positioned aft of said wedge member and disposed with the longer axis of said elipse substantially parallel to the plane of said blade.
 3. The invention of claim 2 including longitudinally extending laterally projecting vanes positioned in a substantially horIzontal plane on opposite sides of said eliptical cone.
 4. The invention of claim 3 wherein said diving vane is inclined at an angle of 17* to 22* with respect to the base of said sled.
 5. The invention of claim 1 including means for releasably connecting a string of pipe to the foot of said blade includes an eye member adapted to receive a tapered pin with rod means connecting said pin to an actuating cam at the top of said blade to permit withdrawing said pin from said eye from a remote location above the earth''s surface. 